The first function of a stopper member is to enable fluid stored in the reservoir on which the stopper member is mounted to be dispensed selectively.
The stopper member of the present invention forms a stopper member of the kind that can be qualified as “inert”, in that it incorporates neither a pump nor a valve. In other words, the fluid is not put under pressure in an inner chamber formed by the stopper member. The stopper member of the present invention is rather similar to a conventional closure device comprising a dispenser orifice that can be closed by means of a stopper.
However, an inherent problem with “inert” closure devices resides in the fact that it is difficult to assure the user that the stopper member has never been opened in order to dispense fluid. The user who purchases a fluid dispenser wants to be assured that the dispenser has never been used beforehand. In order to mitigate that problem, there already exist in the prior art numerous first-use guarantee systems that are associated with the stopper member. For example, it is possible to envelop the stopper member in a film that must be torn on first use in order to be able to access the stopper member. Screw-on stopper members can incorporate a first-use guarantee strip that prevents the plug from being unscrewed. During first use, the user pulls off the strip, or forces the stopper open, thereby destroying the strip. The stopper member of the present invention is not of the screw-on type, and such a pull-off or destroyable peripheral strip is not appropriate for the present invention.